Originally Posted by
gsa103
The primary advantage of an air fork is that the pressure can be adjusted specifically for an individual riders weight. If you want a more plush ride, let some air out, firmer ride, up the pressure. Coil forks work very well, but only if the rider is within about 20lbs of the "design" weight, there's no adjustment for rider weight.
RockShox used to sell 5 different springs to accommodate varying rider weights. Suntour doesn't sell alternate springs. Personally, I'm lighter than the design, so as a result, riding the coil fork is basically just riding a heavy rigid fork.
Great point. I have found that the preload adjustment can be a crude compensator. I'm 230 pounds, and I have the preload all the way out ("loose") on the Suntour NEX fork on my Trek Verve. The fork does compress more than it should when I mount (between 1/3 and 1/2), but the trails I ride do not have severe bumps and the tradeoff is I'm just more careful when I do take it offroad in exchange for the plusher ride. (I don't "ride hard" in general anyway.) I have adjusted the preload all the way in ("tight") before, and it certainly influences the ride -- you described it well -- it's almost like riding a rigid fork. It's not a true lockout, but it works almost like one. Again, I keep it all the way out to get the benefits of the suspension.
My wife's Trek 7100 has an even-cheaper RST suspension fork, and it's clearly tuned for a lighter rider. When I sit on the bike, I compress the fork at least halfway. The ride is, naturally, super plush, but I can make it bottom out on things like driveway ramps. This one doesn't have a preload adjustment, so you just get what you get. The spring rate suits her well at her weight, so it ends up working fine for her.
It would be cool if one could easily replace the springs on these inexpensive forks. But that would pretty clearly add cost to the design, and I understand why that feature isn't there.